The purpose of this study is to address questions on how collectivistic and individualistic cultures affect majority influence in a group decision making task when there are differences in media richness. We developed a theory that explains and predicts these phenomena, and tested hypotheses using 112 four-person groups that consisted of Chinese and U.S. participants. As predicted, we found strong evidence indicating that there were significant differences between Chinese and U.S. groups, with Chinese groups being more prone to follow the view of majority. Further, traditional face-to-face (FtF) unsupported groups experienced the strongest majority influence. We found that GSS use helped diminish majority influence in both Chinese and U.S. groups. These findings have broad theoretical and applied implications, which are discussed in this paper.